Many power saws are known, comprising two reciprocating sawblades supported by a guidebar extending in front of the motor unit. The guidebar is often made with a groove in which the thin upper parts of the sawblades slide in opposite directions. This type of power saw has low vibrations and low resultant forces in use. Examples of this type of saw are found in the patents U.S. Pat. Nos. 1,491,134 and 2,840,125, and British Patent 2, 134,038.
The sawblades are in sliding contact with each other to avoid sawdust and fibers penetrating between the blades, which could pry them apart and make them stick in the groove. In the known saws the force from the outer layers of the guidebar is transmitted to ledges running the whole length of the sawblades on the outside, which helps to maintain the contact between the blades. Such ledges can be created by milling in thick material, by joining layers of thin material or by bending or folding a single layer of thin material as described in application SE 86 04232-2.
Ledges which are continuous but with varying width to facilitate the sawdust transport from selected teeth are described in patent U.S. Pat. No. 2,840,122.
One problem with continuous ledges is that they are difficult to lubricate except by oil supply to the guidebar groove, which requires some kind of a pump. Another problem is that trapped particles of dirt on the ledges are not automatically expelled.
The purpose of the present invention is to make possible a low cost sawblade which can be lubricated from the outside, and which has self-cleaning ledges. It is particularly suited to sawblades with teeth of another material than the body of a sawblade, especially tungsten carbide teeth.